The invention has been devised primarily, although not exclusively, for the testing of components in automatic fire sprinkler systems. In such systems, particular examples of components whose correct operation may require to be tested are flow detectors and one-way valves. The former may simply fail to operate as required, while the latter may stick. Fire sprinkler systems present special problems as compared with, for example, water supply systems for other purposes, in that they are required to function correctly when required to do so in an emergency, but might remain unused for long periods of time. Thus they are required to be tested at regular intervals and hitherto such testing has been carried out by the running off of a quantity of water. This is wasteful of water, and has a further disadvantage in that it usually requires attendance of personnel at, possibly, a large number of places in the system.
Accordingly it is the object of the present invention to provide for the overcoming or reduction of these disadvantages.